Method for treatment and prevention of deficiencies of vitamins B12, folic acid, and B6

ABSTRACT

A method for orally administering vitamin preparations is described which combine vitamin B 12  (B 12 , cobalamin) and folic acid (folate), with and without pyridoxine (B 6 ), for preventing and treating elevated serum homocysteine (HC), cystathionine (CT), methylmalonic acid (MMA), or 2-methylcitric acid (2-MCA) levels. These metabolites have been shown to be indicative of B 12  and/or folic acid deficiencies. Further, it is likely that a B 6  deficiency may be present with a B 12  or folate deficiency. The method of the invention is also for use in lowering serum HC, CT, MMA, or 2-MCA in patients with or at risk for neuropsychiatric, vascular, renal or hematologic diseases. One embodiment of the invention is the use of a non-prescription formulation containing 2.0 mg B 12  and 0.4 mg folic acid, with and without 25 mg B 6 . Another embodiment uses a prescription strength formulation containing 2.0 mg B 12  and 1.0 mg folic acid, with and without 25 mg B 6 . The method of the present invention eliminate the costly and time consuming steps of distinguishing between vitamin deficiencies once a deficiency is found by measurement of serum metabolite levels. The present invention is of particular benefit to the populations at risk for elevated serum metabolite levels, such as the people over the age of 65, and populations that have or are at risk for neuropsychiatric, vascular, renal and hematologic diseases.

The present application is a continuation-in-part of application no. 07/727,628 filed Jul. 10, 1991, now U.S. Pat. No. 5,374,560 which is a continuation-in-part of application no. 333,124 filed Apr. 3, 1989, now abandoned, and application no. 345,885 filed May 1, 1989, now abandoned, which is a continuation-in-part of application no. 933,553 filed Nov. 20, 1986 and now issued as U.S. Pat. No. 4,940,658 on Jul. 10, 1990.

FIELD OF THE INVENTION

This invention relates to the field of nutrition. Specifically, the invention is comprised of new oral vitamin preparations combining vitamin B₁₂ (B₁₂, cobalamin) and folic acid (folate), and vitamin B₁₂, folate, and pyridoxine (B₆) for use in patients with elevated serum metabolite levels of homocysteine (HC), cystathionine (CT), methylmalonic acid (MMA), or 2-methylcitric acid (2-MCA). The elevation of these metabolites has been shown to be indicative of tissue deficiencies of B₁₂ and/or folate and/or B₆, and related to increased risk of neuropsychiatric, vascular, renal and hematologic diseases. One embodiment of the present invention uses a non-prescription formulation comprising between 0.3-10.0 mg B₁₂ and 0.1-0.4 mg folate, with the preferred embodiment using 2.0 mg B₁₂ and 0.4 mg folate. Another embodiment of the non-prescription formulation uses 0.3-10 mg B₁₂, 0.1-0.4 mg folate, and 5-75 mg B₆, with the preferred embodiment using 2.0 mg B₁₂, 0.4 mg folate, and 25 mg B₆. Another embodiment of the present invention uses a prescription strength formulation comprising between 0.3-10.0 mg B₁₂ and 0.4-1.0 mg folate, with the preferred embodiment using 2 mg B₁₂ and 1.0 mg folate. In a further embodiment of the present invention, a prescription strength formulation is used comprising 0.3-10 mg B₁₂, 0.4-1.0 mg folate, and 5-75 mg B₆, with the preferred embodiment using 2 mg B₁₂, 1.0 mg folate, and 25 mg B₆. The formulations of the present invention eliminate the costly and time-consuming steps of distinguishing between vitamin deficiencies once a deficiency is found by measurement of serum metabolite levels. The present invention is of particular benefit to the populations at risk for tissue deficiencies of B₁₂, folate, and B₆, such as people over the age of 65, and populations that have or are at risk for neuropsychiatric, vascular, renal and hematologic diseases.

BACKGROUND

Vitamins B₁₂, folate, and B₆ are required cofactors in metabolic pathways involving methionine, homocysteine, cystathionine, and cysteine. B₁₂ in the form of 5'-deoxyadenosylcobalamin is an essential cofactor in the enzymatic conversion of methylmalonylCoA to succinylCoA. The remethylation of homocysteine (HC) to methionine catalyzed by methionine synthase requires folate (methyltetrahydrofolate) and B₁₂ in the form of methylcobalamin. HC is condensed with serine to form cystathionine (CT) in a reaction catalyzed by cystathionine β-synthase which requires B₆ (pyridoxal phosphate). CT is hydrolyzed in another B₆ -dependent reaction to cysteine and α-ketobutyrate.

It is important to diagnose and treat B₁₂, folate, and B₆ deficiencies because these deficiencies can lead to life-threatening hematologic abnormalities which are completely reversible by proper treatment. B₁₂ deficiency is a multisystem disorder with extremely varied clinical presentation which has been thought to occur in 0.4% of the population, e.g., about 1 million people in the United States. Symptoms of B₁₂ deficiency include significant anemia, displayed for example in decreased hematocrit (e.g., <25%) or hemoglobin (e.g., ≦8 g %), with macrocytic red blood cells (i.e., mean cell volume generally greater than 100 fl), or neurologic symptoms of peripheral neuropathy and/or ataxia. See, for example, Babior and Bunn (1983) in Harrison's Principles of Internal Medicine, (Petersdorf et al., eds.), McGraw-Hill Book Co., New York; Lee and Gardner (1984) in Textbook of Family Practice, 3rd Ed. (Rakel, ed.), Saunders & Co., Philadelphia). The hematological abnormalities seen are due to intracellular folate deficiency since folate is required for a number of essential enzymatic reactions involved in DNA and RNA synthesis and since the form of folate in serum (5-methyltetrahydrofolate) must be metabolized to tetrahydrofolate by the B₁₂ -dependent enzyme methionine synthase before it can be utilized by the RNA- and DNA-related enzymes. While it has been well recognized that individuals with B₁₂ deficiency could display neurologic disorders in the absence of anemia, such situations were believed to be exceptional and rare. See, Beck (1985) in Cecil Textbook of Medicine, 17th Ed., (Wyngaarden and Smith, eds.), W. B. Saunders, Philadelphia, pp. 893-900; Babior and Bunn (1987) in Harrison's Principles of Internal Medicine., 11th Ed., (Braunwald et al., eds.) McGraw-Hill, New York, pp. 1498-1504; Walton (1985) in Brain's Diseases of the Nervous System, 9th Ed., Oxford University Press, Oxford, UK. The neurologic symptoms of B₁₂ deficiency were considered to be late manifestations of the disease most typically occurring after the onset of anemia or, if they occurred first, were soon to be followed by the onset of anemia. See, Woltmann (1919) Am. J. Med. Sci. 157:400-409; Victor and Lear (1956) Am. J. Med. 20:896-911.

However, it has recently been shown that the textbook description of severe megaloblastic anemia and combined systems disease of the nervous system is the rarest presentation of B₁₂ deficiency at the present time (Stabler et al. (1990) Blood 76:871-881; Carmel (1988) Arch. Int. Med. 148:1712-1714; Allen (1991) in Cecil Textbook of Medicine, 19th Ed., (Wyngaarden and Smith, et al. eds.), W. B. Saunders, Philadelphia, pp. 846-854.). Therefore, contrary to previous teachings, patients that may benefit from B₁₂ therapy may have minimal to no hematologic changes while manifesting a wide variety of neurologic and psychiatric abnormalities (Lindenbaum et al. (1988) N. Engl. J. Med. 318:1720-1728; Greenfield and O'Flynn (1933) Lancet 2: 62-63). This is particularly true for populations at risk for B₁₂ deficiency, such as the elderly population (Pennypacker et al. (1992) J. Am. Geriatric Soc. 40: (in press).

The incidence of folate deficiency in the population is unknown, but has been thought to occur commonly in individuals with various degrees of alcoholism. The hematologic abnormalities seen with folate deficiency, such as macrocytic anemia, are indistinguishable from those seen with B₁₂ deficiency. Folate is required for a number of essential enzymatic reactions involved in DNA and RNA synthesis, and is particularly important in rapidly dividing cells like those in the bone marrow.

B₆ is required for the first step in heme synthesis and serves a major role in transamination reactions of amino acid metabolism, in decarboxylations, and in the synthesis of the neuroactive amines histamine, tyramine, serotonin, and γ-aminobutyric acid (GABA). Clinical manifestations include microcytic hypochromic anemia, characteristic skin changes of dermatitis and acrodynia, muscular weakness, and a variety of neuropsychiatric abnormalities including hyperirritability, epileptiform confusions, depression and confusion (Newberne and Conner (1989) in Clinical Biochemistry of Domestic Animals, Academic Press, San Diego, pp. 796-834).

Vitamin deficiencies are generally determined by measurement of serum levels. Normal serum B₁₂ levels are 200-900 pg/ml, with levels of less than 100 pg/ml being said to indicate clinically significant deficiency (Beck (1985) supra) However, serum B₁₂ levels are a relatively insensitive determinant of B₁₂ deficiency in that only 50% of patients with clinically confirmed B₁₂ deficiency have levels less than 100 pg/ml, 40% are 100-200 pg/ml, and at least 5-10% have values in the 200-300 pg/ml range. Diagnosis is further complicated by the fact that 2.5% of normal subjects (6,250,000 people in the U.S.) have low serum B₁₂ levels (Allen (1991) supra), with no evidence of B₁₂ deficiency and are unlikely to benefit from B₁₂ therapy (Schilling et al. (1983) Clin. Chem. 29:582; Stabler (1990) supra).

Normal serum folate levels are 2.5-20 ng/ml, with levels less than 2.5 ng/ml indicating the possibility of clinically significant deficiency. Like B₁₂ serum levels, however, serum folate levels are a relatively insensitive measure in that only 50-75% of patients with folate deficiency have levels less than 2.5% ng/ml, with most of the remaining 25-50% being in the 2.5-5.0 ng/ml range (Allen (1991) in Cecil Textbook of Medicine, 19th Ed., supra).

The development of sensitive serum metabolite assays for HC, CT, MMA, and 2-MCA has allowed the relationship between metabolite levels and vitamin deficiencies to be investigated (Stabler et al. (1987) Anal. Biochem. 162:185-196; Stabler et al. (1986) J. Clin. Invest. 77:1606-1612; Stabler et al. (1988) J. Clin. Invest. 81:466-474). It has been found that elevated serum levels of HC and MMA are clinically useful tests of functional intracellular deficiencies of B₁₂ and folate, with elevated HC levels seen with both B₁₂ and folate deficiencies, and elevated MMA levels seen with a B₁₂ deficiency (Allen et al. (1990) Am. J. Hematol. 34:90-98; Lindenbaum et al. (1990) Am. J. Hematol. 34:99-107; Lindenbaum et al. (1988) N. Engl. J. Med. 318:1720-1728; Beck (1991) in Neuropsychiatric Consequences of Cobalamin Deficiency, Mosby Year Book 36:33-56; Moelby et al. (1990) 228:373-378; Ueland and Refsum (1989() J. Lab. Clin. Med. 114:473-501; Pennypacker et al. (1992) supra). Increased serum levels of CT are seen in both deficiencies and 2-MCA is elevated in B₁₂ deficiency (Allen et al. (1991) in Proceedings of the 1st International Congress on Vitamins and Biofactors in Life Science, Kobe (Japan); Allen et al. (1993) Metabolism (in press)). HC and CT may be elevated in patients with intracellular deficiency of B₆, but this has not been as well documented (Park and Linkswiler (1970) J. Nutr. 100:110-116; Smolin and Benvange (1982) J. Nutr. 112:1264-1272).

Elevated serum metabolite levels are observed in disease states other than classic vitamin deficiencies. For example, elevated HC levels have been observed in the presence of vascular disease. The homocysteine theory of atherosclerosis, formulated by McCully and Wilson (1975) Atherosclerosis 22:215-227, suggests that high levels of HC are responsible for the vascular lesions seen in homocystinuria, a genetic defect caused by a deficiency in the enzyme cystathionine β-synthase. The theory also implies that moderate elevations of HC might be associated with increased risk for vascular disease (Ueland et al. (1992) in Atherosclerotic Cardiovascular Disease, Hemostasis, and Endothelial Function (Francis, Jr., ed.), Marcel Dekker, Inc., New York, pp. 183-236). Moderate hyperhomocysteinaemia has been shown to be frequently present in cases of stroke and to be independent of other stroke risk factors (Brattstrom et al. (1992) Eur. J. Clin. Invest. 22:214-221). Clinical and experimental evidence demonstrates that patients who are homozygotes for cystathionine β-synthase deficiency have a markedly increased incidence of vascular disease and thrombosis. A number of studies (see, Clarke et al. (1991) N. Engl. J. Med. 324:1149-1155) strongly suggest that heterozygotes for a deficiency of cystathionine β-synthase also have an increased incidence of vascular disease and thrombosis and that such heterozygotes may constitute as many as one-third of all patients who develop strokes, heart attacks, or peripheral vascular disease under age 50. It is also likely that such heterozygotes are also at increased risk for vascular disease and thrombosis after age 50. Since the incidence of heterozygosity for cystathionine β-synthase deficiency is estimated to be 1 in 60-70, this means that there are approximately 4 million heterozygotes in the U.S. It is also possible that patients with vascular disease due to other causes, such as hypercholesterolemia, would also benefit from a decrease in their serum HC levels even if their existing levels are only slightly elevated or actually within the normal range.

Renal disease is another condition that gives rise to elevated levels of serum metabolites. Approximately 75% of patients with renal disease have elevated serum concentrations of HC, CT, MMA, and 2-MCA. Since patients with renal disease have a significant incidence and marked acceleration of vascular disease, it might be beneficial to lower their serum metabolite levels, especially that of HC.

An increasing prevalence of low serum B₁₂ concentrations with advancing age has been found by many but not all investigators (Bailey et al. (1980) J. Am. Geriatr. Soc. 28:276-278; Eisborg et al. (1976) Acta Med. Scand. 200:309-314; Niisson-Ehle et al. (1989) Dig. Dis. Sci. 34:716-723; Norman (1985) 33:374; Hitzhusen et al. (1986) Am. J. Clin. Pathol. 85:3236), folate (Magnus et al. (1982) Scan. J. Haematol. 28:360-366; Blundell et al. (1985) J. Clin. Pathol. 38:1179-1184; Elwood et al. (1971) Br. J. Haematol. 21:557-563; Garry et al. (1984) J. Am. Geriatr. Soc. 32:71926; Hanger et al. (1991) J. Am. Geriatr. Soc. 39:1155-1159), and B₆ (Ranke et al. (1960) J. Gerontol. 15:41-44; Rose et al. (1976) Am. J. Clin. Nutr. 29:847-853; Baker et al. (1979) J. Am. Geriatr. Soc. 27:444-450). Moreover, prevalence estimates for these vitamin deficiencies vary widely depending on the population groups studied. It has been unclear whether this increased prevalence is a normal age related phenomena or a true reflection of tissue vitamin deficiency and whether the low serum vitamin concentrations are a reliable indicator of functional intracellular deficiency.

It is difficult, expensive and time-consuming to distinguish between deficiencies of vitamins B₁₂, folate, and B₆. The hematologic abnormalities seen with B₁₂ deficiency are indistinguishable from those seen with folate deficiency. Similarly to a B₁₂ deficiency, B₆ deficiencies also result in hematologic as well as neuropsychiatric abnormalities. The traditional methods of determining deficiencies by measurement of serum vitamin levels are often insensitive. As a result, in order to determine if and which vitamin deficiency is present, a patient will be treated with one vitamin at a time and the response to that vitamin determined by normalization of serum vitamin levels and the correction of hematologic abnormalities. These steps are then repeated with each vitamin. This method of treatment is both expensive and time-consuming. In the presence of multiple deficiencies, the diagnosis of vitamin deficiencies is further confused and give rise to the dangerous possibility that only one deficiency will be treated. For example, the hematologic abnormalities seen with a B₁₂ deficiency will respond to treatment with folate alone. However, the neuropsychiatric abnormalities caused by the B₁₂ deficiency will not be corrected and may indeed by worsened.

It has now been discovered for the first time that the prevalence of intracellular deficiencies of vitamins B₁₂, folate, and B₆, alone or in combination, is substantially higher than that previously estimated by measurement of serum vitamin concentrations. The present disclosure establishes that tissue deficiencies of one or more of the vitamins B₁₂, folate and B₆, as demonstrated by the elevated metabolite concentrations, occurs commonly in the elderly population even when serum vitamin levels are normal. Based on this new discovery, the present invention addresses the problem of distinguishing between vitamin deficiencies when low, low-normal, or normal serum vitamin concentrations are found by providing formulations for the treatment of high serum metabolites and at-risk populations for combinations of one or more tissue deficiencies of vitamins B₁₂, folate, and B₆.

Hathcock and Troendle (1991) JAMA 265:96-97, have suggested the treatment of pernicious anemia with an oral pill containing 300 to 1000 ug or more per day of B₁₂. However, contrary to the present invention, Hathcock and Troendle teach away from combining B₁₂ therapy with folate, since "if the oral cobalamin therapy should fail to maintain adequate levels, folate might provide protection against development of anemia while permitting nerve damage from cobalamin deficiency."

U.S. Pat. No. 4,945,083, issued Jul. 31, 1990 to Jansen, entitled: Safe Oral Folic-Acid-Containing Vitamin Preparation, describes a oral vitamin preparation comprising 0.1-1.0 mg B₁₂ and 0.1-1.0 mg folate for the treatment or prevention of megaloblastic anemia. This formulation presents a problem in the case of a B₁₂ deficient patient, in that the 0.5 mg folate may correct the hematologic abnormalities present, but the 0.5 mg B₁₂ dose may be insufficient to correct a B₁₂ deficiency due to inadequate intrinsic factor. By contrast, the formulation of the present invention teaches the use of the combination of B₁₂ and folate, and of B₁₂, folate and B₆, sufficient to treat either single or multiple deficiencies of B₁₂, folate, and B₆. The present invention does not rely on the determination of vitamin deficiencies by the measurement of serum vitamin levels, but uses the more sensitive measurement of elevated serum metabolites of HC, CT, MMA, and 2-MCA, shown to be related to the presence of B₁₂ and/or folate and/or to B₆ deficiencies or to the presence of the increased risk of neuropsychiatric, vascular, renal, and hematologic diseases.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed.

SUMMARY OF THE INVENTION

This invention includes a method for orally administering two new vitamin preparations containing vitamin B₁₂ and folate, and vitamin B₁₂, folate and B₆, for the treatment of patients with elevated serum metabolites, such as homocysteine, cystathionine, methylmalonic acid, and 2-methylcitric acid, as well as populations at risk for tissue deficiencies in one or more of the vitamins B₁₂, folate, and B₆ or for neuropsychiatric, vascular, renal, or hematologic diseases.

One embodiment of the present invention is uses an over-the-counter formulation comprised of between 0.3-10 mg CN-cobalamin (B₁₂) and 0.1-0.4 mg folate. Another embodiment of the non-prescription formulation uses 0.3-10 mg B₁₂, 0.1-0.4 folate, and 5-75 mg B₆. Preferred embodiments of the over-the-counter formulation are comprised of about 2.0 mg B₁₂ and 0.4 mg folate, and 2.0 mg B₁₂, 0.4 mg folate, and 25 mg B₆, respectively.

Another embodiment of the present invention uses a prescription formulation comprised of between 0.3-10 mg CN-cobalamin (B₁₂) and 0.4-10.0 mg folate. Another embodiment of the prescription formulation of the present invention uses 0.3-10 mg B₁₂, 0.4-1.0 mg folate, and 5-75 mg B₆. Preferred embodiments of the prescription formulation use about 2.0 mg B₁₂ and 1.0 mg folate, and 2.0 mg B₁₂, 1.0 mg folate, and 25 mg B₆, respectively.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the distribution of serum B₁₂ levels for a population of elderly outpatients (ages 65-99, n=152) and a normal population (ages 17-65, n=100).

FIG. 2 shows serum MMA levels for a population of elderly outpatients with serum B₁₂ values <300 pg/ml (ages 65-99, n=38/152) and a normal population with serum B₁₂ values <300 pg/ml (ages 17-65, n=10/100).

FIG. 3 shows serum HC levels for a population of elderly outpatients with serum B₁₂ values <300 pg/ml (ages 65-99, n=38/152) and a normal population with serum B₁₂ values <300 pg/ml (ages 17-65, n=10/100).

FIG. 4 shows serum MMA levels before and after treatment with parenteral cobalamin for a population of elderly outpatients with elevated MMA values and serum B₁₂ values <300 pg/ml (ages 65-99, n=15/38).

FIG. 5 shows serum HC levels before and after treatment with parenteral cobalamin for a population of elderly outpatients with elevated HC values and serum B₁₂ values of <300 pg/ml (ages 65-99, n=10/38).

FIG. 6 shows the distribution of serum B₁₂ levels for a population of elderly nursing home patients (ages 55-107, n=212) and a normal population (ages 17-65, n=100) .

FIG. 7 shows serum MMA levels for a population of elderly nursing home patients with serum B₁₂ values <300 pg/ml (ages 55-107, n=29/212) and a normal population with serum B₁₂ values (ages 17-65, n=10/100).

FIG. 8 shows serum HC levels for a population of elderly nursing home patients with serum B₁₂ values <300 pg/ml (ages 55-107, n=29/212) and a normal population with serum B₁₂ values <300 pg/ml (ages 17-65, n=10/100).

FIG. 9 shows serum MMA levels before and after treatment with parenteral cobalamin for a population of elderly nursing home patients with serum B₁₂ values <300 pg/ml (ages 55-107, n=14/29).

FIG. 10 shows serum HC levels before and after treatment with parenteral cobalamin for a population of elderly nursing home patients with serum B₁₂ values <300 pg/ml (ages 55-107, n=14/29).

FIG. 11 shows the distribution of serum B₁₂ levels for a population of elderly patients (ages 65-99, n=548) and a normal population (ages 22-63, n=117) (Framingham study).

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the presently preferred embodiments of the invention, which, together with the following examples, serve to explain the principles of the invention.

This invention uses new oral vitamin formulations combining vitamin B₁₂ (B₁₂, cobalamin) and folic acid (folate), and vitamin B₁₂, folate and pyridoxine (B₆). The formulations of the present invention are for use in the treatment of elevated serum levels of one or more the metabolites homocysteine (HC), cystathionine (CT), methylmalonic acid (MMA), or 2-methylcitric acid (2-MCA). The use of the formulations of the present invention further include as a method of lowering serum metabolites levels of one or more of HC, CT, MMA, or 2-MCA, where these metabolite levels are not elevated but the patients are at risk for or have neuropsychiatric, vascular, renal, or hematologic diseases.

One embodiment of the present invention uses a non-prescription formulation comprised of between about 0.3-10 mg CN-cobalamin (B₁₂) and 0.1-0.4 mg folate. Another embodiment of the present invention uses a non-prescription formulation comprised of between about 0.3-10 mg B₁₂, 0.1-0.4 mg folate, and 5-75 mg B₆. Preferred embodiments of the non-prescription formulation are comprised of about 2.0 mg B₁₂ and 0.4 mg folate, and 2.0 mg B₁₂, 0.4 mg folate, and 25 mg B₆, respectively.

Another embodiment of the present invention is comprised of a prescription formulation comprised of between about 0.3-10 mg B₁₂ and 0.4-10.0 mg folate, with the preferred embodiment comprised of about 2.0 mg B₁₂ and 1.0 mg folate. Another embodiment of the prescription strength formulation is comprised of about 0.3-10 mg B₁₂, 0.4-10.0 mg folate, and 5-75 mg B₆, with a preferred embodiment comprised of about 2.0 mg B₁₂, 1.0 mg folate, and 25 mg B₆.

The formulations of the present invention are for the treatment and prevention of elevated metabolite levels in at risk populations, such as the elderly, and people that have or are at risk for neuropsychiatric, vascular, renal and hematologic diseases. The present invention eliminates the costly and time consuming need to differentiate between B₁₂, folate, and B₆ deficiencies.

The administration of a daily dose of the vitamin formulations of the present invention provides better long-term normalization of serum HC and other metabolites than prior art formulations, and eliminates the difficulty in differentiating between deficiencies of two or three of the vitamins, the difficulty in diagnosing multiple deficiencies of two or three of the vitamins, and the expense of doing so. Further, the administration of an oral preparation of B₁₂ and folate, with or without B₆, is preferred over intramuscular injections for patient convenience and ease of administration.

For example, the inclusion of B₁₂ will be useful as a safeguard for patients misdiagnosed as folate deficient, even though they are actually B₁₂ deficient, since treatment with folate alone in such patients is extremely dangerous. The danger arises from the fact that treating a B₁₂ deficient patient with folate alone may reverse or prevent the hematologic abnormalities seen in B₁₂ deficiency, but will not correct the neuropsychiatric abnormalities of a B₁₂ deficiency and may actually precipitate them. Even in the absence of intrinsic factor, approximately 1% of a 2.0 mg oral dose of B₁₂ is absorbed by diffusion. Thus, approximately 20 ug of B₁₂ would be absorbed from the formulations of the present invention which would be more than adequate even in patients with pernicious anemia who have lost their intrinsic factor-facilitated absorption mechanism for B₁₂. The inclusion of folate will be of benefit since B₁₂ deficiency causes a secondary intracellular deficiency of folate. The inclusion of folate and B₆ will also be of benefit in patients with mixed vitamin deficiencies.

The formulations of the present invention may be administered as a non-injectable implant or orally. Non-injectable use may be as a patch. Formulations for oral administration are preferably encapsulated. Preferably, the capsule is designed so that the formulation is released gastrically where bioavailability is maximized. Additional excipients may be included to facilitate absorption of the vitamin formulations. Diluents, flavorings, low melting point waxes, vegetable oils, lubricants, suspending agents, tablet disintegrating agents, and binders may also be employed.

Example 1 describes the methods used to measure serum vitamin and metabolite levels. Example 2 describes a new study conducted with 412 subjects over the age of 65 with a variety of medical conditions correlating the incidence of low serum vitamin levels with elevated serum metabolite levels. A study determining the incidence of undetected B₁₂ deficiency and response of serum MMA and HC to B₁₂ treatment in a geriatric outpatient population is described in Example 3. Example 4 describes a similar study conducted with a geriatric nursing home population, and Example 5 describes a similar study conducted with another geriatric population.

EXAMPLE 1 Methods for Measurement of Serum Vitamin and Metabolite Levels

Serum vitamin assays

Serum vitamins B₁₂ and folate were measured by a quantitative radioassay method using purified intrinsic factor and purified folate binding protein. Vitamin B₆ was measured by a radioenzymatic assay method wherein serum is incubated with apoenzyme tyrosine-decarboxylase, C₁₄ labelled tyrosine is added to start the enzymatic reaction which is stopped with HCl. Subsequently the free C₁₄ -labelled CO₂ is adsorbed by a KOH impregnated filtering paper. The measured C₁₄ activity is directly proportional to the B₆ (pyridoxal phosphate) concentration (Laboratory Bioscientia, Germany).

Serum metabolite assays

Serum metabolite assays for homocysteine and methylmalonic acid were conducted by the capillary gas chromatography and mass spectrometry methods of Marcell et al. (1985) Anal. Biochem. 150:58; Stabler et al. (1987) supra, and Allen et al. (1990) Am. J. Hematol. 34:90-98. Serum cystathionine levels were assayed by the method of Stabler et al. (1992) Blood (submitted). Serum 2-methylcitric acid was assayed by the method of Allen et al. (1993) Metabolism supra.

Statistical methods

Statistical analysis was done with the SAS statistical package (version 6.06). Nonparametric data for two or more groups were tested with the two sample Wilcoxon rank sum test (with Bonferroni's correction for the significance level α) and the Kruskall Wallis test. From the result of the healthy young subjects reference intervals were calculated. Since the frequency distribution of the values of each parameter were markedly abnormal they were transformed to normal distributions using log transformation. The sample prevalence p with 95% confidence intervals of low serum vitamins B₁₂, folate, and B₆ concentrations was calculated as (p±2 p (1-p)/n×100 wherein n is the total sample size, p is the number of low serum vitamin concentrations/n; low serum concentrations are defined as <mean-2 S.D.

EXAMPLE 2 Incidence of Elevated MMA, 2-MCA, HC, and CT Levels in the Geriatric Population

The serum concentrations of B₁₂, folate, and B₆ were measured in 412 subjects over the age of 65 (subgroups A-D), and in 99 healthy control subjects aged 20-55 years (subgroup E). The geriatric subgroups were defined as follows: A, 110 patients with atherosclerosis; B, 98 patients with neuropsychiatric disorders; C, 102 patients with atherosclerosis and multiple diseases including rheumatoid arthritis and diabetes; D, 102 subjects who were healthy.

Venous blood was obtained from all subjects in the morning after an overnight fast. The blood was spun within one hour after collection and the serum was transported in dry ice to the central laboratory. Serum vitamins B₁₂ and folate were measured as described in Example 1 with a vitamin B₁₂ /folate dual RIA kit (CT301/CT302 Amersham Buchier, UK). Vitamin B₆ and serum metabolites were measured as described in Example 1.

Since renal function can influence serum metabolite concentrations (Ueland and Refsum (1989) supra; Moelby et al. (1992) Scand. J. Clin. Lab. Invest. 52:351-354), serum creatinine concentrations were measured in all subjects by the Jaffe photometric method (Laboratory Bioscientia, Germany). Normal range was 62-124 μmol/L. Creatine clearance was calculated using the formulation of Cockroft and Gault (1976) Nephron 16:31-41.

Normal ranges for serum vitamin and metabolite levels were determined by the mean±2 standard deviations after log normalization using the values from subgroup E. Results are shown in Table 1:

                  TABLE 1                                                          ______________________________________                                         INCIDENCE OF LOW SERUM VITAMIN AND HIGH                                        METABOLITE LEVELS IN GERIATRIC POPU-                                           LATIONS A-D AND A YOUNGER HEALTHY                                              POPULATION E.                                                                               Folic                                                             Group B.sub.12                                                                              Acid   B.sub.6                                                                              MMA   2-MCA   HC   CT                                ______________________________________                                         A     6%     12%    48%   36%   44%     55%  64%                               B     6%     19%    53%   47%   39%     59%  66%                               C     3%     10%    50%   32%   45%     39%  73%                               D     6%      6%    17%   26%   23%     38%  41%                               E     2%      1%     1%    3%    6%      2%   4%                               ______________________________________                                    

There was a rough correlation with low vitamin levels and elevated metabolites, but many of the patients with elevated metabolites had low normal or normal vitamin levels. Correlations between clinical abnormalities within groups A, B, and C were not present. Patients were treated with weekly injections of a multi-vitamin preparation containing 1.0 mg B₁₂, 1.1 mg folate, and 5 mg B₆, resulting in a marked lowering or normalization of elevated metabolite levels in virtually every elderly patient.

These data support the conclusions that there is an increased incidence of low levels of serum B₁₂, folate, and B₆ in the geriatric population, and that serum MMA, 2-MCA, HC and CT are elevated in an even higher percentage of geriatric patients. The presence of elevated levels of one or more of the metabolites HC, CT, MMA, or 2-MCA indicate a tissue or intracellular deficiency of one or more of the vitamins B₁₂, folate and B₆. It not possible to tell without expensive, time-consuming, and extensive testing which one vitamin or pair of vitamins, or whether all three vitamins are deficient. These observations, together with the fact that elevated metabolite levels are corrected by parenteral therapy with a combination of vitamins B₁₂, folate, and B₆, indicate that a tissue deficiency of one or more of these vitamins occurs commonly in the geriatric population and that measurement of serum vitamin levels alone is an inadequate method for identifying such deficiencies.

EXAMPLE 3 Determination of Serum B₁₂, Folate, MMA, HC, CT and 2-MCA Levels in a Geriatric Outpatient Population

A study was conducted with 152 elderly outpatient subjects to measure the prevalence of B₁₂ deficiency in geriatric outpatients as determined by both low serum B₁₂ levels and elevations of MMA and HC, and to determine the response to B₁₂ treatment. Blood samples were obtained on 152 consecutive geriatric outpatients, ages 65-99. Control values were determined from 100 subjects, ages 17-65. Serum B₁₂, folate, MMA, HC, CT, and 2-MCA levels were obtained for each patient, shown in Table 2. The significance of the results marked as "**" in Table 2 are as follows: B₁₂ levels of <200 pg/ml; folate<3.8 ng/ml; homocysteine>16.2 uM; MMA>271 nM; CT>342 nM; and 2-MCA>228 nM. Serum MMA, HC, CT, and 2-MCA levels were measured as described in Example 1. Serum B₁₂ and folate were measured as described in Example 1 using a Corning Immophase kit (CIBA-Corning, Medfield, Mass.) with the normal range defined as 200-800 pg/ml for B₁₂ and 3.8 ng/ml for folate. After evaluation, patients received weekly parenteral cyanocobalamin injections (1,000 ug IM) for 8 weeks, followed by monthly injections. Repeat laboratory and clinical assessments were administered at 8 weeks and at 6 months.

Results show that 25% of the subjects had a serum B₁₂ level ≦300 pg/ml and 8.5% had a low level of <200 pg/ml. FIG. 1 shows the shift seen in elderly subject towards lower serum B₁₂ levels. More than half of the subjects with low or low-normal serum B₁₂ levels had elevations of MMA (FIG. 2) and/or HC (FIG. 3) greater than 3 S.D. above the means in normals and representing 14.5% of the total screened population.

Patients with low and low/normal serum B₁₂ levels were treated with weekly injections of 1.0 mg B₁₂. Parenteral B₁₂ administration caused elevated metabolite levels to fall to or towards normal (FIGS. 4 and 5) in every subject treated with B₁₂. It appears that the true prevalence of previously unrecognized B₁₂ deficiency in this elderly populations was at least 14.5%.

It can be seen from the data presented in Table 2 that serum B₁₂ levels are insensitive for screening B₁₂ deficiencies since similar numbers of patients with low normal serum B₁₂ levels of 201-300 pg/ml compared with patients with low B₁₂ levels (≦200 pg/ml) had markedly elevated metabolites which fell with B₁₂ treatment. Further, this study shows that elderly patients have a high incidence (at least 14.5%) of unrecognized B₁₂ deficiency, detectable by measurement of serum HC and MMA levels in patients with serum B₁₂ levels <300 pg/ml.

A further finding in this study emphasizes the need to treat elevated metabolite levels with a combination of vitamin B₁₂ and folate with or without B₆. Some of the patients exhibiting elevated metabolite levels did not fully respond to B₁₂ treatment. This may indicate a concomitant deficiency of folate and/or B₆. The lack of response to B₁₂ treatment could result from a deficiency of one, a pair, or all three vitamins. However, it would be expensive and time-consuming to attempt to distinguish between the vitamin deficiencies.

Another, and perhaps the most important, finding in this study is the large number of patients with serum B₁₂ ≦300 pg/ml who have elevated values for one or more metabolites as indicated by a "**" next to the individual values. As can readily be seen in Table 2, there are many examples of elevated value for MMA and/or 2-MCA at all levels of serum B₁₂ including the mid-normal (300-600 pg/ml), the high-normal (600-800 pg/ml), and even the elevated (>800 pg/ml) ranges. The same is true for elevations of HC and CT. In some patients the serum folate is low, indicating that folate deficiency may be present, but in many cases both B₁₂ and folate levels are normal. B₆ levels were not performed in this study, but B₆ deficiency would not be expected to cause elevations of MMA or 2-MCA. Thus in many patients it is not clear which vitamin, or pair of vitamins, or whether all three vitamins is or are deficient. One could pick a single vitamin, often at random, with which to treat a patient for several weeks or months, and then repeat measurement of metabolite levels to determine if a partial or full correction had occurred. If there was no response, one could try another vitamin, or if there was a partial response one could add a second vitamin, and then repeat metabolite measurement after several weeks or months. If there was still no response, one could try the third vitamin, or if there was a partial response, one could try a different pair of vitamins. Eventually one could determine whether an individual vitamin, a particular pair of vitamins, or all three vitamins were required to normalize or maximally reduce the metabolite levels, but it would often require months or even a year to make this determination. Such a determination would be expensive. In addition, a patient who was optimally treated with a single vitamin or pair of vitamins might subsequently develop a deficiency of one or even two of the other vitamins as evidenced by a re-elevation or increase in the levels of one or more metabolites. Therapeutic testing could be reinitiated and continued as described above, although this would also be time-consuming and expensive.

It requires less time and expense to treat patients with elevated metabolite levels with a combination of vitamin B₁₂ and folate, or a combination of vitamin B₁₂, folate and vitamin B₆. The utility of the approach of the present invention is appreciated only after it is taught, for the first time in the present disclosure, that a deficiency of one or more of the three vitamins occurs commonly in the elderly population as evidenced by elevation of one or more metabolites, i.e., MMA, 2-MCA, HC and CT.

EXAMPLE 4 Determination of Serum B₁₂, Folate, MMA, and HC Levels in a Geriatric Nursing Home Population

A study was conducted with 212 elderly nursing home patients to determine serum B₁₂, folate, MMA, and HC levels (Table 3). The significance of the results shown in Table 3 marked with "**" are as described for Table 2 (Example 3). The control group consisted of 100 subjects between the ages of 17-65 years. As in the study described in Example 3, the elderly population exhibited a shift to lower serum B₁₂ levels (FIG. 6), elevated serum MMA (FIG. 7) and HC (FIG. 8) levels. Parenteral administration of B₁₂ 1 mg per week for 8 weeks to those with serum B₁₂ <300 pg/ml caused elevated MMA (FIG. 9) and HC (FIG. 10) levels to fall to or towards normal.

As in the study reported in Example 3, a further finding in this study emphasizes the need to treat elevated metabolite levels with a combination of vitamins B₁₂ and folate, with or without B₆. Some of the patients exhibiting elevated metabolite levels did not fully respond to B₁₂ treatment. This may indicate a concomitant deficiency of folate and/or B₆. The lack of response to B₁₂ treatment could result from a deficiency of one, a pair, or all three vitamins. However, it would be expensive and time-consuming to attempt to distinguish between the vitamin deficiencies.

Again, an important finding in this study is the large number of patients with serum B₁₂ >300 pg/ml who have elevated values for one or more metabolites as indicated by a "**" next to the individual values. As is seen in Table 3, there are many examples of elevated values for MMA at all levels of serum B₁₂ including the mid-normal (300-600 pg/ml), the high-normal (600-800 pg/ml), and even the elevated (>800 pg/ml) ranges. The same is true for elevations of HC. In some patients the serum folate is low, indicating that folate deficiency may be present, but in many cases both B₁₂ and folate levels are normal. B₆ levels were not performed in this study, but B₆ deficiency would not be expected to cause elevations of MMA. Thus, again it is not clear which vitamin, or pair of vitamins, or whether all three vitamins is or are deficient. One could pick a single vitamin with which to treat a patient for several weeks or months, and then repeat measurement of metabolite levels to determine if a partial or full correction had occurred. If there was no response, one could try another vitamin, or if there was a partial response one could add a second vitamin, and then repeat metabolite measurement after several weeks or months. If there was still no response, one could try the third vitamin, or if there was a partial response, one could try a different pair of vitamins. Eventually one could determine whether an individual vitamin, a particular pair of vitamins, or all three vitamins were required to normalize or maximally reduce the metabolite levels, but it would often require months or even a year to make this determination. Such a determination would be expensive. In addition, a patient who was optimally treated with a single vitamin or pair of vitamins might subsequently develop a deficiency of one or even two of the other vitamins as evidenced by a re-elevation or increase in the levels of one or more metabolites. Therapeutic testing could be reinitiated and continued as described above, although this would also be time-consuming and expensive.

It requires less time and expense to treat patients with elevated metabolite levels with a combination of vitamin B₁₂ and folate, or a combination of vitamin B₁₂, folate and vitamin B₆. The utility of the approach of the present invention is appreciated only after it is taught, for the first time in the present disclosure, that a deficiency of one or more of the three vitamins occurs commonly in the elderly population as evidenced by elevation of one or more metabolites, i.e., MMA, 2-MCA, HC and CT.

EXAMPLE 5 Determination of Serum B₁₂, Folate, MMA, and HC Levels in a Geriatric Population

A study was conducted with 548 elderly subjects from the Framingham study between the ages of 65-99 to determine serum B₁₂, folate, MMA, and HC levels (Table 4). The significance of the results shown in Table 4 (marked with "**") are as described for Table 2 (Example 2).

As in the study described in Examples 3 and 4, the elderly population exhibited a shift to lower serum B₁₂ levels (FIG. 11), and elevated serum MMA and HC levels. The elderly population also exhibited a high incidence (9.5%) of low serum folate levels (Table 4). As in the studies reported in Examples 2, 3 and 4, the incidence of tissue or intracellular vitamin deficiencies based on elevated metabolite levels was higher than that predicted from measurement of serum vitamin levels.

As in Examples 3 and 4 above, these results confirm the importance of the finding that there are a large number of patients with serum B₁₂ >300 pg/ml who have elevated values for one or more metabolites as indicated by a "**" next to the individual values. As is seen in Table 4, there are many examples of elevated MMA values at all levels of serum B₁₂ including the mid-normal (300-600 pg/ml), the high-normal (600-800 pg/ml), and even the elevated (>800 pg/ml) ranges. The same is true for elevations of HC. In some patients the serum folate is low, indicating that folate deficiency may be present, but in many cases both B₁₂ and folate levels are normal. B₆ levels were not performed in this study, but B₆ deficiency would not be expected to cause elevations of MMA. Thus, again it is not clear which vitamin, or pair of vitamins, or whether all three vitamins is or are deficient. One could pick a single vitamin with which to treat a patient for several weeks or months, and then repeat measurement of metabolite levels to determine if a partial or full correction had occurred. If there was no response, one could try another vitamin, or if there was a partial response one could add a second vitamin, and then repeat metabolite measurement after several weeks or months. If there was still no response, one could try the third vitamin, or if there was a partial response, one could try a different pair of vitamins. Eventually one could determine whether an individual vitamin, a particular pair of vitamins, or all three vitamins were required to normalize or maximally reduce the metabolite levels, but it would often require months or even a year to make this determination. Such a determination would be expensive. In addition, a patient who was optimally treated with a single vitamin or pair of vitamins might subsequently develop a deficiency of one or even two of the other vitamins as evidenced by a re-elevation or increase in the levels of one or more metabolites. Therapeutic testing could be reinitiated and continued as described above, although this would also be time-consuming and expensive.

It requires less time and expense to treat patients with elevated metabolite levels with a combination of vitamin B₁₂ and folate, or a combination of vitamin B₁₂, folate and vitamin B₆. The utility of the approach of the present invention is appreciated only after it is taught, for the first time in the present disclosure, that a deficiency of one or more of the three vitamins occurs commonly in the elderly population as evidenced by elevation of one or more metabolites, i.e., MMA, 2-MCA, HC and CT.

                  TABLE 2                                                          ______________________________________                                         SERUM METABOLITE & VITAMIN LEVELS IN A                                         GERIATRIC OUTPATIENT POPULATION.                                                                      Homo-              Total                                Patient                                                                              B12      Folate  cysteine                                                                              MMA   CT    MC                                   ______________________________________                                         116     66**   9.8     41.8** 1508**                                                                               507** 759**                                118     79**   9.3     29.6** 2200**                                                                               343** 428**                                016    155**   7.6     15.3   1316**                                                                               208   196                                  067    163**   6.6     9.9    93    164   69                                   091    178**   12.0    29.2** 3108**                                                                               438** 318**                                042    181**   11.3    13.0   452** 300   262**                                030    185**   6.6     26.0** 282** 310   223                                  037    187**   9.4     12.3   160   218   334**                                100    187**   9.5     13.6   208   453** 141                                  036    188**   9.9     16.3** 298** 385** 322**                                109    189**   7.6     12.3   127   188   161                                  007    191**   11.7    67.1** 6349**                                                                               619** 1005**                               018    193**   5.8     16.7** 412** 272   235**                                050   210      4.0     25.3** 464** 727** 121                                  108   214      6.0     31.1** 264   523** 315**                                041   216      7.2     19.1** 418** 360** 288**                                126   224      6.5     8.8    103   361** 121                                  005   231      12.5    17.1** 269   825** 276**                                024   235      13.0    18.5** 2946**                                                                               232   289**                                111   237      6.3     14.6   135   380** 203                                  023   239      4.1     21.9** 385** 775** 279**                                010   256      12.9    11.5   652** 119   144                                  055   258      6.8     7.5    189   342   185                                  102   259      10.9    23.9** 1894**                                                                               423** 400**                                026   260      18.5    20.4** 1949**                                                                               295   248**                                107   262      13.1    10.1   231   628** 153                                  038   269      7.6     15.7   222   152   152                                  140   277      4.0     29.1** 744** 602** 254**                                074   278      5.2     24.1** 699** 296   187                                  002   278      14.6    14.8   554** 259   277**                                019   282      8.5     12.4   329** 262   161                                  035   287      5.8     9.8    230   390** 218                                  049   290      3.9     33.0** 140   275   138                                  078   290      10.9    12.5   197   240   209                                  045   291      8.7     9.5    162   613** 132                                  092   294      14.9    19.3** 500** 246   167                                  137   297      6.8     10.1   631** 340   184                                  072   298      6.7     19.7** 375** 302   246**                                149   310      8.3     16.1   314** 199   149                                  047   312      4.9     15.9   277** 271   173                                  060   312      9.4     8.0    100   228   203                                  046   314      6.5     16.2   142   336   125                                  093   318      6.4     16.5** 304** 361** 130                                  014   321      14.5    10.7   275** 233   170                                  088   327      7.1     17.8** 263   507** 258**                                032   340      6.6     8.6    150   133   133                                  147   347      7.6     18.2** 305** 219   265**                                001   351      4.7     20.8** 199   402** 223                                  090   353      4.9     20.7** 144   419** 178                                  008   358      5.4     11.6   372** 529** 177                                  104   360      12.7    12.1   260   89    77                                   110   370      3.0**   17.1** 456** 297   150                                  103   371      18.7    14.5   257   219   180                                  056   373      6.5     12.4   236   415** 189                                  048   374      3.6**   9.7    167   237   230**                                131   377      10.9    13.6   256   220   85                                   122   378      7.6     21.9** 906** 227   196                                  004   385      8.6     10.3   109   288   92                                   120   390      9.8     22.9** 499** 529** 260**                                138   405      6.9     14.7   334** 238   188                                  141   407      8.1     14.3   168   259   263**                                101   408      5.9     9.2    160   134   40                                   145   410      3.7**   25.4** 567** 550** 349**                                027   415      11.1    10.6   169   278   164                                  028   418      5.6     34.6** 608** 589** 351**                                011   420      10.6    18.8** 683** 1014**                                                                               282**                                081   421      6.6     16.5** 861** 641** 531**                                033   423      4.2     16.3** 156   194   170                                  057   425      18.3    13.5   209   381** 321**                                021   427      18.9    12.1   223   524** 168                                  135   430      8.8     13.5   284** 412** 180                                  097   435      15.4    10.9   353** 465** 119                                  052   438      6.8     5.2    281** 372** 238**                                132   448      12.6    16.8** 1931**                                                                               394** 250**                                086   451      12.1    6.6    139   208   107                                  148   458      13.9    11.4   187   322   238**                                012   466      15.3    8.3    560** 250   144                                  083   466      12.0    13.7   366** 214   193                                  133   470      13.8    10.8   290** 275   55                                   017   475      4.0     39.6** 196   467** 220                                  053   476      13.4    12.3   226   206   125                                  009   482      6.5     25.3** 240   470** 214                                  066   498      9.6     12.9   374** 233   92                                   031   507      11.0    14.8   173   278   220                                  099   507      10.4    9.6    124   233   63                                   128   507      4.6     9.4    294** 324   176                                  013   514      11.3    15.9   163                                              151   522      7.8     14.3   370** 324   215                                  077   523      6.8     17.7** 184   210   214                                  079   523      15.6    13.0   316** 223   251**                                054   524      4.9     10.0   148   230   123                                  020   524      9.9     14.2   235   366** 190                                  069   528      7.0     9.7    257   281   83                                   085   536      4.0     22.5** 97    191   114                                  084   551      14.2    12.5   166   179   131                                  082   559      12.3    14.6   208   371** 182                                  117   560      3.4**   18.8** 102   176   88                                   061   561      12.7    9.8    170   404** 152                                  006   567      4.6     16.8** 138   688** 165                                  129   567      4.9     16.2   363** 495** 331**                                003   570      11.4    12.9   189   330   230**                                115   576      6.3     17.8** 128   231   95                                   089   578      10.3    12.0   147   258   236**                                143   581      2.6**   42.7** 165   555** 208                                  114   583      5.1     16.6** 599** 660** 177                                  080   593      9.5     18.0** 208   289   142                                  015   598      7.0     12.4   167   381** 95                                   039   598      9.6     18.1** 691** 719** 354**                                070   612      5.6     13.7   197   296   82                                   051   622      12.9    8.3    119   246   150                                  139   628      8.5     7.8    145   166   83                                   150   628      8.6     14.5   295** 315   183                                  043   635      5.9     13.7   239   272   189                                  096   651      17.4    9.7    326**                                            073   657      7.0     9.5    186   283   78                                   127   665      5.8     8.1    166   344** 147                                  121   677      10.2    9.5    226   346** 173                                  034   694      15.9    12.1   406** 592** 584**                                124   697      9.7     11.0   63    179   60                                   123   702      10.4    10.6   186   148   96                                   113   705      7.6     8.4    107   534** 92                                   071   709      10.6    11.3   207   584** 141                                  076   722      8.1     10.5   271   489** 138                                  044   724      7.3     12.1   212   683** 217                                  040   731      15.1    7.4    205   149   136                                  062   741      4.4     18.7** 153   856** 416**                                025   741      10.0    12.2   224   344** 121                                  119   755      5.9     10.1   187   377** 61                                   075   757      10.0    24.7** 246   345** 276**                                098   759      13.8    13.9   380** 239   156                                  134   769      7.5     10.4   125   131   81                                   087   773      25.0    10.1   181   285   135                                  142   788      4.6     12.1   166   273   129                                  064   792      15.4    8.6    218   299   139                                  094   793      16.6    10.0   186   179   173                                  022   808      8.8     14.4   184   271   161                                  112   812      12.0    9.2    181   184   108                                  125   817      14.4    11.0   158   242   72                                   106   862      5.3     9.2    94    300   95                                   146   890      13.9    11.9   135                                              058   897      5.3     18.5** 154   460** 80                                   063   943      17.8    19.7** 277** 642** 306**                                095   960      25.3    10.7   135   181   111                                  152   963      9.4     8.8    198                                              130   971      15.9    13.5   106   307   84                                   059   1063     9.4     9.7    129   378** 54                                   105   1109     11.0    6.1    87    155   64                                   136   1163     6.0     13.1   250   565** 122                                  065   1251     14.5    10.7   88    147   88                                   029   1490     22.2    9.7    129   111   105                                  144   1536     7.0     17.7** 216   694** 418**                                068   1809     12.7    10.4   59    128   39                                   ______________________________________                                    

                  TABLE 3                                                          ______________________________________                                         SERUM METABOLITE & VITAMIN LEVELS IN A                                         GERIATRIC NURSING HOME POPULATION.                                             Patient                                                                              B12      Folate   Homocysteine                                                                            Methylmalonic Acid                            ______________________________________                                         NH170   8**    14.0     34.8**   3365**                                        NH129   40**   7.4      40.9**   6245**                                        NH156   44**   22.4     17.4**   1130**                                        NH139   56**   9.7      20.9**   1180**                                        NH132   67**   7.6      92.4**   12641**                                       NH176  129**   9.2      20.3**   1156**                                        NH196  136**   6.2      41.0**   1077**                                        NH109  139**   9.8      20.9**   1294**                                        NH203  146**   4.3      12.2     437**                                         NH141  161**   13.4     12.2     223                                           NH178  172**   8.2      5.9      141                                           NH103  189**   5.5      13.1     362**                                         NH181  196**   6.3      14.7     296**                                         NH160 206      11.9     12.5     640**                                         NH197 221      24.0     10.5     654**                                         NH073 222      3.6**    19.8**   490**                                         NH110 227      5.5      13.7     1297**                                        NH010 228      4.0      21.1**   413**                                         NH012 234      8.7      16.0     596**                                         NH037 236      11.5     22.5**   11299**                                       NH114 238      12.8     13.2     442**                                         NH211 240      6.0      14.1     166                                           NH075 250      9.3      12.1     170                                           NH172 255      7.2      14.4     552**                                         NH148 259      5.7      19.2**   317**                                         NH138 264      9.2      16.7**   340**                                         NH150 264      4.0      13.7     98                                            NH099 272      5.5      12.5     125                                           NH124 275      6.9      11.5     87                                            NH179 301      7.6      7.1      143                                           NH135 302      6.5      23.4**   397**                                         NH087 304      7.8      10.8     327**                                         NH180 304      5.8      10.5     237                                           NH209 306      7.6      11.9     105                                           NH107 310      3.3**    8.6      148                                           NH081 320      4.3      23.6**   470**                                         NH068 324      7.9      13.4     243                                           NH183 325      7.7      11.1     144                                           NH033 330      13.8     7.7      149                                           NH161 333      8.5      11.3     385**                                         NH192 337      10.7     9.5      209                                           NH136 340      6.7      18.2**   409**                                         NH191 342      20.2     13.4     271                                           NH137 343      4.0      15.6     183                                           NH182 346      8.2      14.4     448**                                         NH020 347      8.4      10.4     149                                           NH165 351      18.5     11.8     425**                                         NH095 352      8.5      14.5     366**                                         NH194 361      4.3      20.3**   305**                                         NH106 362      4.8      12.9     298**                                         NH060 367      4.7      16.4**   71                                            NH009 368      5.1      15.9     325**                                         NH071 382      4.9      12.9     330**                                         NH080 390      6.1      15.0     171                                           NH013 407      6.7      12.4     310**                                         NH126 409      9.2      17.4**   137                                           NH030 411      11.2     10.4     844**                                         NH210 413      8.6      11.9     210                                           NH158 414      5.7      16.2     508**                                         NH027 416      10.2     15.5     769**                                         NH003 424      16.5     9.5      167                                           NH187 429      4.7      8.8      439**                                         NH022 430      10.5     14.0     214                                           NH082 436      10.6     17.7**   340**                                         NH162 438      6.1      19.2**   180                                           NH021 439      5.3      15.1     191                                           NH056 447      11.7     10.9     184                                           NH119 448      3.2**    14.1     241                                           NH120 448      5.6      12.0     138                                           NH186 450      4.7      23.1**   213                                           NH064 451      6.9      10.6     237                                           NH057 453      14.6     10.4     282**                                         NH131 454      8.1      16.2     258                                           NH059 462      6.0      9.1      147                                           NH202 465      3.3**    17.0**   393**                                         NH134 475      15.3     11.6     321**                                         NH083 475      7.4      10.6     178                                           NH199 479      15.1     10.4     141                                           NH042 482      6.0      15.0     141                                           NH200 491      13.6     9.8      154                                           NH213 497      8.1      10.0     92                                            NH143 500      5.2      22.1**   175                                           NH031 502      6.4      16.1     151                                           NH188 504      12.5     15.1     1461**                                        NH171 504      10.7     12.9     344**                                         NH008 505      4.6      9.9      185                                           NH102 506      16.6     9.1      236                                           NH145 512      7.7      22.2**   161                                           NH093 514      5.1      17.7**   185                                           NH118 524      25.0     10.1     314**                                         NH185 524      8.7      12.1     84                                            NH111 527      5.1      18.4**   250                                           NH149 530      12.6     18.2**   531**                                         NH011 534      8.1      12.5     654**                                         NH128 540      4.3      11.6     120                                           NH035 547      7.5      9.8      193                                           NH005 551      17.7     5.0      365**                                         NH212 552      11.9     12.1     202                                           NH007 554      6.4      26.1**   646**                                         NH086 554      9.5      5.1      127                                           NH069 555      22.7     6.8      134                                           NH121 555      8.2      10.0     112                                           NH117 571      6.6      9.7      351**                                         NH055 581      14.8     9.1      265                                           NH025 581      5.2      15.3     181                                           NH104 583      3.9      14.6     1699**                                        NH173 583      11.2     10.6     160                                           NH177 584      6.2      5.7      111                                           NH207 586      8.5      16.4**   243                                           NH070 591      5.4      12.0     168                                           NH038 592      8.0      8.8      230                                           NH049 599      10.7     21.7**   238                                           NH062 606      4.5      7.7      96                                            NH153 608      7.7      13.6     221                                           NH206 611      6.6      16.4**   400**                                         NH018 614      6.3      10.9     123                                           NH163 616      5.0      9.6      132                                           NH189 619      7.6      12.0     158                                           NH045 620      21.0     12.4     265                                           NH074 621      10.2     9.2      172                                           NH054 623      8.0      9.8      121                                           NH152 625      8.2      7.8      206                                           NH140 637      21.7     13.6     300**                                         NH050 642      16.3     13.5     275**                                         NH089 644      7.7      16.7**   444**                                         NH036 649      7.9      10.7     68                                            NH097 651      6.6      13.4     426**                                         NH016 656      4.1      61.0**   356**                                         NH053 657      14.2     10.6     320**                                         NH066 658      7.7      11.4     228                                           NH051 659      4.0      10.7     216                                           NH108 671      5.8      24.0**   823**                                         NH058 673      6.0      11.2     392**                                         NH028 675      22.3     9.1      105                                           NH204 678      4.7      10.2     148                                           NH169 679      6.9      19.2**   267                                           NH032 681      12.7     5.9      99                                            NH065 682      11.0     13.5     176                                           NH061 683      13.4     9.6      190                                           NH116 685      9.0      7.5      244                                           NH015 699      6.8      16.8**   236                                           NH157 711      10.0     12.8     198                                           NH155 715      10.0     17.6**   308**                                         NH034 715      7.9      11.4     179                                           NH040 717      10.5     15.7     256                                           NH105 718      6.0      13.2     308**                                         NH048 719      8.0      10.8     207                                           NH084 720      6.8      9.4      169                                           NH115 724      16.3     9.4      161                                           NH205 734      8.5      13.3     232                                           NH113 738      11.7     10.3     171                                           NH154 738      13.7     9.6      123                                           NH167 741      17.0     6.6      129                                           NH190 752      5.2      14.1     254                                           NH067 760      22.5     9.5      232                                           NH014 767      8.9      7.3      100                                           NH072 768      8.3      6.9      131                                           NH133 772      8.8      20.4**   219                                           NH122 778      6.0      10.4     108                                           NH076 781      12.1     14.9     282**                                         NH147 785      7.5      24.5**   411**                                         NH026 786      9.7      8.3      146                                           NH151 789      24.4     11.1     182                                           NH198 797      10.9     10.7     158                                           NH088 801      6.4      18.3**   184                                           NH004 806      11.3     8.8      96                                            NH024 818      5.1      14.1     219                                           NH100 826      16.4     10.5     103                                           NH078 831      7.2      10.3     266                                           NH052 844      19.6     8.0      193                                           NH142 848      18.6     12.1     398**                                         NH002 862      9.4      11.3     212                                           NH091 891      4.9      12.6     169                                           NH127 897      22.0     8.4      132                                           NH096 901      9.3      5.2      104                                           NH201 910      25.0     15.7     424**                                         NH184 941      21.5     10.8     170                                           NH208 945      20.2     9.8      111                                           NH130 968      22.4     10.4     339**                                         NH164 989      8.0      16.8**   102                                           NH077 1006     15.1     9.2      188                                           NH017 1015     11.9     9.5      175                                           NH029 1053     18.6     11.4     161                                           NH023 1055     9.3      9.7      193                                           NH047 1079     6.4      11.4     106                                           NH043 1082     14.5     13.9     144                                           NH195 1088     36.9     12.2     150                                           NH193 1092     8.2      15.7     225                                           NH046 1093     9.2      18.8**   186                                           NH101 1108     3.9      8.1      139                                           NH098 1117     11.3     12.5     88                                            NH168 1124     25.2     15.0     203                                           NH006 1126     6.9      8.1      159                                           NH144 1135     8.0      21.9**   262                                           NH044 1159     26.8     10.2     109                                           NH175 1162     7.8      12.0     210                                           NH146 1179     9.8      10.1     129                                           NH112 1238     10.3     15.0     347**                                         NH001 1304     13.1     6.9      142                                           NH166 1337     13.4     8.3      67                                            NH079 1346     18.0     12.0     248                                           NH041 1528     20.7     8.2      155                                           NH063 1559     15.0     7.0      66                                            NH159 1566     6.6      15.5     451**                                         NH125 1703     8.2      20.6**   153                                           NH094 1768     15.9     8.4      182                                           NH123 2028     10.2     16.8**   206                                           NH174 2106     13.3     12.8     280**                                         NH039 2227     23.8     8.9      119                                           NH019 2297     11.1     15.5     177                                           NH092 2360     5.7      9.8      131                                           NH085 3141     22.0     26.9**   1947**                                        ______________________________________                                    

                  TABLE 4                                                          ______________________________________                                         SERUM METABOLITE AND VITAMIN LEVELS IN A                                       GERIATRIC POPULATION.                                                          Patient B.sub.12 Folate    Homocysteine                                                                            MMA                                        ______________________________________                                         495       77**   10.0      65.4**   3145**                                     484       84**   10.0      77.5**   6820**                                     522      100**   3.6**     15.5     967**                                      455      115**   1.9**     21.8**   170                                        493      135**   4.4       16.9**   421**                                      528      145**   3.9       38.3**   729**                                      510      155**   4.6       14.1     804**                                      502      155**   2.1**     16.9**   347**                                      412      160**   18.5      33.8**   1301**                                     409      160**   4.8       16.8**   164                                        470      165**   9.2       19.9**   1468**                                     460      165**   6.8       11.5     142                                        437      170**   4.9       16.5**   813**                                      439      170**   1.2**     21.3**   502**                                      525      175**   11.5      15.3     1058**                                     442      175**   4.2       17.5**   328**                                      456      180**   7.3       11.1     206                                        450      180**   5.0       11.8     196                                        477      185**   3.4**     31.4**   369**                                      508      190**   4.1       19.5**   335**                                      423      190**   2.5**     19.0**   329**                                      462      190**   3.8       11.6     276**                                      523      190**   5.6       16.8**   207                                        482      190**   2.9**     25.1**   179                                        459      190**   5.3       19.6**   167                                        543      195**   4.3       13.5     470**                                      520      195**   1.7**     22.2**   309**                                      431      195**   7.2       13.5     251                                        513     200      5.0       25.0**   1184**                                     534     200      4.9       32.6**   1080**                                     515     200      4.9       17.3**   478**                                      531     200      5.1       26.8**   466**                                      516     200      3.6**     17.8**   279**                                      526     200      1.6**     23.5**   171                                        471     205      5.7       22.0**   542**                                      413     205      2.6**     20.4**   304**                                      497     205      3.3**     19.4**   258                                        539     205      4.1       15.4     247                                        544     205      12.5      11.7     233                                        540     205      4.0       17.1**   185                                        517     205      2.2**     15.0     151                                        496     210      3.7**     15.2     1103**                                     488     210      16.5      21.8**   600**                                      416     215      12.5      10.0     197                                        434     220      7.1       24.8**   439**                                      545     220      11.5      14.4     407**                                      547     220      5.3       17.5**   396**                                      408     220      3.2**     16.4**   357**                                      449     220      3.7**     13.7     272**                                      507     220      8.5       10.0     179                                        458     225      10.5      21.1**   964**                                      491     225      7.2       16.0     472**                                      529     230      2.0**     61.1**   1172**                                     415     230      3.2**     28.9**   377**                                      453     230      3.6**     19.8**   336**                                      448     230      5.2       13.1     319**                                      498     230      5.9       20.1**   255                                        533     230      5.7       11.7     151                                        466     235      35.0      12.1     617**                                      537     235      5.7       10.7     394**                                      483     235      8.6       16.6**   344**                                      512     235      3.9       12.5     190                                        452     240      4.7       26.5**   1068**                                     454     240      5.2       11.9     201                                        535     240      4.4       15.3     195                                        421     245      10.5      12.5     464**                                      469     245      6.2       20.0**   448**                                      474     245      7.3       10.3     327**                                      486     245      9.2       12.6     156                                        536     250      22.5      20.3**   1068**                                     475     250      5.6       23.0**   456**                                      511     250      2.7**     23.1**   398**                                      465     250      4.1       23.1**   323**                                      506     250      5.2       11.5     252                                        417     250      5.5       25.2**   241                                        524     250      2.5**     14.4     212                                        411     250      9.9       11.5     200                                        492     250      5.2       10.7     182                                        548     250      2.9**     12.4     179                                        441     250      4.5       8.5      147                                        480     255      4.8       16.9**   558**                                      532     255      7.0       14.8     419**                                      464     255      11.5      12.9     400**                                      494     255      6.2       12.1     293**                                      106     255      4.5       11.7     203                                        546     260      5.5       14.7     662**                                      541     260      5.4       30.8**   426**                                      420     260      5.3       13.6     347**                                      500     260      6.7       14.0     330**                                      538     260      9.3       17.3**   298**                                      457     260      2.9**     12.6     286**                                      472     260      8.3       13.8     278**                                      424     260      8.3       10.1     242                                        433     260      6.8       10.5     197                                        425     265      7.3       14.7     724**                                      468     265      3.8       16.7**   289**                                      435     265      7.4       14.0     150                                        499     265      2.2**     12.4     131                                        432     270      4.3       28.3**   432**                                      521     270      3.7**     15.3     349**                                      549     270      4.1       12.4     343**                                      518     270      10.0      10.1     276**                                      418     270      26.0      9.4      213                                        419     270      6.5       12.5     212                                        428     270      4.2       18.7**   189                                        443     270      8.8       12.0     187                                        446     270      11.0      8.1      157                                        461     275      7.6       15.1     663**                                      440     275      4.9       12.9     248                                        436     275      6.3       30.1**   233                                        530     275      7.4       13.6     231                                        438     275      4.6       8.5      221                                        527     275      7.5       10.5     219                                        444     275      4.0       12.2     180                                        429     280      5.3       15.3     463**                                      503     280      4.4       25.7**   421**                                      485     280      3.5**     15.6     381**                                      410     280      14.5      10.0     201                                        487     280      3.9       10.5     166                                        430     280      9.2       8.8      161                                        519     285      3.9       22.2**   919**                                      476     285      10.5      12.8     339**                                      509     285      5.4       13.0     331**                                      501     285      5.5       12.4     252                                        542     285      6.9       15.5     242                                        445     285      7.2       14.9     237                                        427     285      4.0       17.1**   233                                        490     290      4.7       13.9     230                                        451     290      2.1**     20.0**   226                                        414     290      7.0       9.7      117                                        467     290      4.1       6.5      68                                         463     295      5.8       12.3     296**                                      473     295      7.5       14.4     290**                                      505     295      4.1       12.4     257                                        198     300      11.5      10.9     323**                                      195     300      9.8       12.2     216                                        207     305      7.7       13.2     330**                                       67     305      8.6       15.4     312**                                       50     305      9.0       11.6     235                                         70     305      12.5      12.7     228                                        113     305      5.6       13.5     201                                         39     305      6.9       19.7**   170                                         3      305      4.2       11.5     135                                        325     305      14.5      9.4      94                                         368     310      4.7       15.9     371**                                      322     310      7.8       15.3     362**                                      295     310      7.2       13.8     305**                                      347     310      5.8       16.5**   266                                        313     310      6.1       16.5**   219                                        355     310      5.5       15.4     138                                        291     310      4.5       15.2     125                                        478     315      23.0      17.7**   857**                                       53     315      5.8       12.1     505**                                      240     315      6.7       12.3     394**                                       14     315      9.6       14.2     331**                                      137     315      7.8       24.3**   306**                                      254     315      8.7       17.0**   285**                                      109     315      3.7**     16.5**   263                                        252     315      5.2       10.1     241                                        186     315      4.1       15.4     238                                        183     315      5.5       10.7     195                                        390     315      6.9       10.0     188                                        267     315      2.2**     12.0     124                                        310     320      12.0      13.8     395**                                       31     320      17.0      12.9     334**                                       88     320      4.8       13.8     217                                        403     320      9.6       11.3     162                                         60     320      6.2       11.4     155                                        315     320      6.4       9.9      136                                        175     325      6.3       17.8**   486**                                      317     325      22.0      14.0     294**                                       18     325      6.3       11.1     241                                        247     325      13.5      13.2     231                                        223     325      9.2       12.6     203                                        132     325      3.7**     15.4     184                                        168     325      4.3       10.2     174                                        238     325      5.5       9.9      166                                        117     325      5.2       15.0     154                                        404     330      2.5**     33.1**   1085**                                     138     330      4.8       11.3     360**                                      316     330      3.6**     10.2     272**                                       61     330      5.1       12.5     242                                        333     330      34.0      9.2      235                                         16     330      4.6       13.3     211                                        276     330      5.7       11.9     200                                        391     330      4.1       8.4      184                                        362     330      9.2       11.7     178                                         1      330      9.9       8.9      170                                        379     335      16.0      12.1     471**                                      147     335      9.0       9.7      427**                                       89     335      8.0       15.3     385**                                      211     335      5.0       12.2     374**                                       45     335      5.9       16.3**   250                                         47     335      5.0       13.6     249                                        402     335      4.7       13.5     230                                        314     335      7.6       9.7      203                                        150     335      4.8       11.2     119                                        120     340      1.9**     21.0**   775**                                      284     340      7.2       25.6**   439**                                      230     340      14.0      11.4     419**                                      149     340      8.8       18.9**   337**                                      269     340      3.9       16.2     302**                                      197     340      10.5      12.8     233                                         19     340      9.6       11.0     232                                        422     340      3.1**     14.4     188                                        196     340      11.5      8.9      169                                         40     345      8.7       14.6     610**                                      244     345      8.6       15.8     461**                                      287     345      5.7       18.1**   427**                                      100     345      8.3       14.8     403**                                      383     345      4.3       27.2**   284**                                       62     345      19.5      9.6      250                                        350     345      8.0       10.0     249                                         65     345      8.0       10.2     247                                        307     345      16.5      11.6     208                                         69     345      17.0      9.9      197                                        328     345      7.5       8.9      192                                         43     345      6.0       13.2     191                                        222     345      6.1       9.2      175                                        306     345      4.3       17.2**   160                                        154     345      7.1       10.2     148                                         94     350      4.8       16.1     302**                                      201     350      6.1       9.9      200                                         13     350      5.1       10.9     193                                        236     355      7.2       14.8     309**                                      191     355      5.8       15.3     257                                        481     355      5.2       17.1**   134                                         92     360      4.2       25.2**   321**                                      324     360      3.8       16.6**   264                                         87     360      3.3**     13.3     200                                         46     360      5.4       11.1     179                                        289     360      9.5       7.9      129                                        392     360      5.1       10.3     125                                        320     365      6.4       17.3**   240                                        134     365      13.5      11.8     238                                        239     365      7.7       13.2     236                                        326     365      6.0       10.9     180                                        364     365      4.1       13.9     154                                        218     365      7.5       11.2     126                                        216     365      6.2       12.2     119                                        248     365      5.7       13.3     117                                        375     370      4.1       20.7**   532**                                      288     370      6.4       18.8**   436**                                      161     370      6.3       11.2     340**                                      224     370      19.5      9.8      286**                                      330     370      18.0      12.2     228                                        334     370      12.5      8.7      172                                        275     370      6.9       12.7     162                                         54     375      7.3       10.1     583**                                      185     375      9.3       10.5     386**                                       52     375      8.1       15.5     291**                                      366     375      5.0       12.5     280**                                       93     375      3.3**     16.2     248                                        151     375      2.9**     12.3     235                                         85     375      6.7       14.8     217                                        294     375      7.0       12.2     184                                        361     375      7.9       10.7     179                                        318     375      5.5       13.7     160                                        386     375      7.6       10.4     153                                        304     375      9.1       9.4      132                                        228     380      7.7       17.1**   320**                                      110     380      4.0       7.2      135                                        204     380      5.7       10.6     91                                         348     385      2.3**     17.4**   368**                                      146     385      11.5      12.5     253                                        260     385      5.5       13.7     211                                        136     385      3.6**     19.8**   205                                        338     385      5.0       16.2     180                                        376     385      3.6**     13.7     154                                        194     385      12.5      7.9      153                                        504     385      38.0      9.5      138                                        160     390      8.1       24.7**   475**                                      354     390      11.5      12.8     212                                         25     390      5.1       11.3     205                                        387     390      8.7       8.4      162                                         86     390      21.0      12.6     133                                        133     390      3.9       11.3     113                                        331     395      12.0      20.1**   638**                                      130     395      10.5      10.8     256                                         82     395      2.8**     9.8      236                                        119     395      12.5      16.3**   209                                        380     395      10.5      14.3     159                                        373     395      5.5       11.6     152                                        256     395      10.5      9.9      149                                        384     395      7.3       14.7     116                                        105     400      19.0      10.5     322**                                      251     400      4.8       14.9     289**                                      352     400      11.5      9.6      181                                        279     400      4.5       11.7     170                                        339     400      7.4       13.6     168                                        381     405      6.7       12.4     294**                                      285     405      7.0       14.2     281**                                      340     405      3.6**     19.6**   275**                                       51     405      6.5       14.3     233                                         33     405      6.5       9.6      207                                        268     405      3.3**     14.9     205                                         73     405      5.2       13.1     172                                         17     410      7.5       16.2     473**                                      286     410      4.7       18.8**   415**                                      140     410      5.9       21.7**   302**                                      116     410      6.8       14.5     218                                        396     410      5.6       16.1     190                                        356     410      1.9**     27.6**   149                                        237     410      3.6**     16.6**   122                                        112     410      5.5       8.9      107                                        259     410      4.7       11.6     99                                         176     415      5.2       21.9**   453**                                      193     415      10.5      11.3     163                                        323     415      6.1       9.6      163                                        202     415      11.5      9.4      150                                        398     415      8.0       12.6     134                                        321     420      5.2       10.7     383**                                      142     420      29.0      8.3      234                                        327     420      3.2**     14.6     203                                        342     420      7.3       9.4      156                                        170     420      20.5      10.3     142                                        345     420      29.5      13.2     136                                        302     420      8.6       8.8      128                                        115     425      6.3       22.2**   628**                                       97     425      12.5      19.8**   313**                                      246     425      8.7       15.1     241                                         72     425      10.5      13.5     241                                        365     425      6.7       16.7**   237                                        139     425      12.5      10.4     224                                        143     425      8.1       13.5     216                                        426     425      19.5      14.5     201                                        303     425      3.0**     14.5     154                                        388     425      6.2       12.3     135                                        127     425      6.7       8.4      100                                        262     430      10.0      12.1     323**                                      270     430      4.8       12.9     293**                                      514     430      4.3       12.9     197                                        341     430      3.5**     19.9**   190                                        278     430      5.2       10.8     182                                        370     430      11.0      15.3     174                                         55     430      7.6       11.0     162                                        274     430      5.0       8.2      131                                        367     430      17.5      8.0      126                                         98     430      13.5      12.8     125                                        337     435      13.5      14.1     395**                                      309     435      8.7       12.9     349**                                      305     435      17.5      15.4     187                                        144     435      25.0      8.9      167                                         34     435      8.6       7.6      157                                        234     435      9.7       9.2      116                                        123     440      9.6       12.2     622**                                      200     440      4.8       12.4     257                                        250     440      7.5       12.9     248                                        107     440      6.3       14.7     183                                        300     440      6.5       7.9      123                                        374     445      5.4       14.0     247                                        372     445      11.0      11.0     181                                         36     445      4.0       10.0     181                                        271     445      7.2       10.4     124                                        242     445      15.5      9.6      112                                        264     445      6.0       10.7     100                                        172     450      11.5      14.9     607**                                       32     450      11.5      13.6     362**                                      346     450      13.5      15.8     330**                                       41     450      8.5       11.4     194                                         95     450      5.1       12.5     182                                        357     455      6.3       14.4     296**                                      319     455      17.0      10.2     147                                        308     455      15.0      9.8      131                                        235     455      23.0      9.0      114                                        349     455      9.2       8.3      82                                         178     460      5.6       20.6**   473**                                      312     460      4.7       14.4     197                                         79     460      5.0       10.4     173                                        131     460      18.0      10.2     162                                        243     460      2.6**     11.6     160                                        261     465      7.7       10.6     252                                        378     465      5.4       13.2     221                                         49     465      47.0      10.8     179                                        226     465      7.7       10.2     173                                        377     465      5.6       8.5      143                                        253     465      10.0      7.0      138                                         76     470      12.5      14.8     304**                                      203     470      15.0      7.6      233                                        296     470      23.5      11.0     161                                        382     470      5.3       11.1     109                                         6      475      10.5      12.5     232                                         75     475      4.5       8.1      150                                        332     475      9.4       10.0     144                                        290     475      14.0      9.1      143                                        128     475      5.9       9.3      133                                        124     475      6.0       13.5     111                                        177     475      8.8       9.1      106                                        126     480      11.0      11.0     212                                        283     480      5.2       10.6     175                                        209     480      10.5      10.5     175                                        293     480      6.8       15.5     135                                        121     485      4.7       20.0**   345**                                      282     485      12.0      10.9     236                                         71     485      13.5      8.1      168                                        385     485      9.0       14.1     128                                        190     495      9.9       10.4     410**                                      210     495      8.6       12.0     243                                        155     495      5.9       10.4     219                                        336     495      13.5      9.9      135                                        280     500      8.7       14.5     334**                                       96     500      4.7       10.8     237                                        145     500      5.9       17.5**   233                                        199     500      4.2       13.8     199                                        489     500      11.5      9.7      198                                        217     500      6.4       9.6      166                                         90     500      7.5       8.5      106                                        164     510      5.2       23.8**   408**                                      343     510      4.5       13.7     284**                                       42     510      4.9       7.4      233                                        351     510      8.5       11.0     207                                        299     510      12.0      8.0      104                                         99     520      10.5      25.8**   322**                                      114     520      30.0      10.9     220                                        369     520      29.0      16.7**   206                                         37     520      10.5      8.6      191                                        215     520      6.7       16.8**   151                                        401     520      7.5       12.6     148                                        229     520      7.9       11.0     116                                        135     520      3.2**     8.3      88                                          81     530      6.8       14.8     372**                                       91     530      14.5      10.6     228                                        167     530      23.5      9.2      176                                        181     530      5.5       9.3      171                                         56     530      20.0      8.3      163                                         5      530      13.5      8.1      159                                        180     540      12.0      9.0      216                                        311     540      4.1       13.3     214                                        389     540      3.9       13.9     169                                        125     540      5.5       13.0     159                                         35     540      22.5      11.0     123                                        104     550      10.5      16.5**   544**                                      393     550      4.9       11.9     339**                                      394     550      23.0      14.0     278**                                      292     550      6.9       16.2     263                                        163     550      6.7       14.3     219                                         66     550      10.5      11.6     206                                         29     550      17.5      9.6      191                                        227     550      7.9       11.7     154                                         38     550      7.5       11.9     152                                        241     550      10.5      9.8      100                                        102     550      9.7       8.6      91                                          77     560      24.0      14.8     554**                                      162     560      10.5      11.8     275**                                      273     560      8.7       9.4      180                                         80     560      6.3       11.2     108                                        255     560      8.8       9.9      93                                         122     570      66.0      13.8     304**                                      208     570      34.0      10.2     255                                         23     570      21.5      8.3      241                                        447     570      25.0      10.0     164                                        225     570      5.7       12.2     154                                        174     570      7.1       11.0     127                                         11     570      19.0      8.9      113                                        165     580      10.5      14.8     226                                        182     580      8.9       8.2      189                                        245     590      15.5      10.0     262                                         83     590      17.5      8.3      199                                        166     590      11.5      9.4      188                                        158     590      7.3       10.7     166                                        187     590      4.5       11.0     146                                        156     590      23.5      11.3     112                                        231     600      9.5       9.0      192                                         78     600      11.5      9.4      151                                        329     610      15.0      7.3      312**                                       57     610      16.0      11.9     286**                                       7      610      12.0      10.4     195                                        277     610      9.5       7.8      153                                        108     620      13.5      8.4      191                                        205     620      18.0      7.5      145                                        263     620      9.8       10.2     101                                         9      630      4.9       11.4     300**                                      111     630      8.3       11.1     276**                                       68     630      11.5      8.9      143                                        399     630      14.0      11.0     90                                         266     640      5.1       15.7     364**                                       12     640      24.5      9.0      233                                        152     640      8.1       10.0     209                                        405     640      7.0       12.8     186                                         27     640      22.5      8.4      136                                        258     640      8.3       11.2     120                                        249     640      8.7       9.1      81                                         297     650      16.0      10.0     279**                                      192     650      4.9       14.9     213                                        257     650      3.3**     16.3**   208                                        184     650      12.5      9.9      193                                         58     650      18.5      10.7     172                                        301     650      16.0      15.5     162                                        397     650      12.5      8.4      146                                        272     650      11.0      7.4      120                                        153     650      7.1       13.1     116                                        406     650      6.6       5.8      81                                          10     660      9.0       7.6      154                                         26     660      22.0      8.3      132                                        265     670      3.9       19.3**   509**                                      359     670      21.0      8.3      269                                         48     670      32.0      9.9      262                                        335     670      11.5      8.1      121                                        189     680      6.6       17.9**   358**                                      220     680      15.5      10.9     115                                         15     690      13.5      13.4     159                                         44     700      20.0      12.7     244                                         21     700      13.5      10.2     129                                         74     700      15.0      7.1      65                                          4      710      29.0      8.5      266                                        353     710      11.5      11.4     206                                        281     710      10.5      9.6      185                                         2      710      8.0       8.5      109                                        212     740      20.0      11.1     250                                         8      740      12.0      11.5     216                                        206     750      12.5      8.3      116                                        101     770      14.5      12.7     372**                                      344     770      32.0      11.7     297**                                       20     770      35.0      10.1     245                                        407     770      10.5      12.0     110                                        360     780      2.7**     20.9**   157                                        232     790      15.5      10.1     151                                        141     790      12.5      9.5      74                                         129     800      8.7       11.7     211                                        188     800      15.0      12.3     174                                        400     800      12.5      10.3     156                                         24     810      23.0      7.5      194                                        173     830      35.0      11.4     243                                        214     830      21.5      12.0     187                                         63     830      13.8      8.8      185                                        148     830      45.0      7.1      146                                         84     830      23.5      7.0      136                                        179     830      16.5      6.6      96                                         171     840      23.5      11.2     195                                         28     870      5.8       15.9     197                                        233     870      7.9       12.7     169                                        221     870      40.0      7.0      126                                        371     880      20.0      8.5      152                                        213     890      10.5      18.0**   231                                        358     900      21.0      8.3      149                                        298     910      15.5      10.2     221                                        118     910      100.0     9.7      170                                        479     950      11.5      12.1     188                                         30     950      6.2       10.5     170                                        159     1000     9.5       8.7      281**                                      219     1050     37.0      14.3     313**                                      103     1050     12.5      10.3     154                                         59     1150     17.5      7.3      180                                        157     1250     12.0      14.0     206                                        363     1350     28.0      10.4     190                                         22     1400     13.5      10.4     233                                         64     1400     31.0      9.7      149                                        169     1450     15.0      9.5      150                                        ______________________________________                                     

We claim:
 1. A method for treating or preventing a deficiency in a host of at least one of cobalamin, folate or B₆ comprising determining the level of at least one metabolite selected from the group consisting of homocysteine, cystathionine, and 2-methylcitric acid, and administering to the host a formulation containing cobalamin, folate and B₆, only if the level of at least one of said metabolites is elevated.
 2. The method of claim 1, wherein said administering step includes administering between 0.1 and 10.0 mg cobalamin, between 0.1 and 10 mg of folate, and between 5 and 75 mg B₆.
 3. The method of claim 2, wherein said administering step includes administering between 0.1 and 0.4 mg of folate.
 4. The method of claim 2, wherein said administering step includes administering between 0.4 and 10 mg of folate.
 5. The method of claim 1, wherein said administering step includes administering between 0.1 and 10 mg cobalamin and between 0.1 and 10 mg. folate.
 6. The method of claim 5, wherein said administering step includes administering between 0.1 and 0.4 mg of folate.
 7. The method of claim 5, wherein said administering step includes administering between 0.4 and 10 mg. of folate.
 8. The method of claim 1, wherein said determining step includes determining the level of homocysteine.
 9. The method of claim 1, wherein said determining step includes determining the level of cystathionine.
 10. The method of claim 1, wherein said determining step includes determining the level of 2-methylcitric acid. 